The invention relates to a side chain test system and method for the security and stability of a smart contract. The system comprises a first module which is used for receiving the smart contract issued by a first user, wherein when a second user can determine whether to join a test under the condition that the smart contract is acquired, and a third user in the block chain network bifurcates a main chain to form a side chain and arranges the smart contract on the side chain; a second module which is used for transferring part or all of assets of the second user from a main chain to a side chain and generating a corresponding mirror image user under the condition that the second user determines to participate in the smart contract test, and is used for authorizing the third user to mine onthe side chain; a third module which is used for receiving vulnerabilities, released by the second user in the testing process, in the smart contract and voting when the total calling frequency of the smart contract reaches a preset value and can be used for publishing the vulnerabilities and the votes to a fourth module.